Genetics

The replication of DNA is...

• conservative
• dispersive
• semi-conservative
• random

Which of the following is not a post-transcriptional modification of mRNA?

• addition of poly-A tail
• addition of 5' cap
• removal of introns
• removal of exons

A mutation leading to an early 'stop' codon is a ...

• frameshift mutation
• silent mutation
• missense mutation
• nonsense mutation

The two strands in a DNA molecule are held together by ...

• hydrogen bonds
• phosphodiester bonds
• covalent bonds
• ionic bonds

Since most amino acids are encoded for by more than one codon, the genetic code is said to be ...

• semi-conservative
• a triplet code
• universal
• redundant

Which of the following statements about histones is FALSE?

• They have a positive charge.
• They are made of nucleic acids.
• They consist of basic amino acids.
• They attract DNA.

The synthesis of a new strand of DNA ...

• starts at an operator sequence.
• involves DNA ligase.
• is always in fragments.
• occurs from the 5' end to the 3' end.

RNA is similar to DNA in that ...

• it is a polymer of nucleotides
• it is double-stranded 
• it is only found in the nucleus
• there is only one type of RNA

A codon is to mRNA as an anti-codon is to ...

• DNA
• an amino acid
• rRNA
• tRNA

Which of the following statements about ribosomes is FALSE?

• They have 3 'sites' - E, P and A sites.
• They read mRNA from the 3' end to the 5' end.
• They consist of 2 subunits.
• They make proteins.